While working on the Rust support, I happened to notice that arch_type
and related functions take "char *" arguments, where "const char *"
would be more correct. This patch fixes this oversight. Tested by
rebuilding.
2016-06-10 Tom Tromey <tom@tromey.com>
* gdbtypes.c (arch_type, arch_integer_type, arch_character_type)
(arch_boolean_type, arch_float_type, arch_complex_type)
(arch_flags_type, append_flags_type_field)
(append_flags_type_flag, arch_composite_type)
(append_composite_type_field_raw)
(append_composite_type_field_aligned)
(append_composite_type_field): Make "name" parameter const.
* gdbtypes.h (arch_type, arch_integer_type, arch_character_type)
(arch_boolean_type, arch_float_type, arch_complex_type)
(append_composite_type_field, append_composite_type_field_aligned)
(append_composite_type_field_raw, arch_flags_type)
(append_flags_type_field, append_flags_type_flag): Constify.
PR rust/20110 concerns the type of an integer constant that is too
large for "i32", the default integer type. This patch changes the
type of such a constant to i64. This is important because such values
are often addresses, so truncating them by default is unfriendly.
Built and regtested on x86-64 Fedora 23.
2016-06-10 Tom Tromey <tom@tromey.com>
PR rust/20110:
* rust-exp.y (lex_number): Don't truncate large numbers to i32.
2016-06-10 Tom Tromey <tom@tromey.com>
PR rust/20110:
* gdb.rust/expr.exp: Add test for integer constant larger than
i32.
I noticed that the rust-exp handling in the Makefile differed from
that of other .y files. I believe I noticed this by seeing a stray
"rm" in the build log.
This patch changes the Makefile to bring the rust-exp handling in line
with that of other .y files.
2016-06-10 Tom Tromey <tom@tromey.com>
* Makefile.in (COMMON_OBS): Remove rust-exp.o.
(YYFILES): Add rust-exp.c.
(YYOBJ): Add rust-exp.o.
(local-maintainer-clean): Remove rust-exp.c.
Non-local references in nested functions are usually implemented
by using DWARF static link. This feature was added
with commit 63e43d3aedb8b1112899c2d0ad74cbbee687e5d6
(DWARF: handle non-local references in nested functions) but
a testcase was missing in Fortran.
2016-06-10 Bernhard Heckel <bernhard.heckel@intel.com>
gdb/Testsuite/Changelog:
* gdb.fortran/nested-funcs.exp: New.
* gdb.fortran/nested-funcs.f90: New.
This change adds support for specifying a negative repeat count to
all the formats of the 'x' command to examine memory backward.
A new testcase 'examine-backward' is added to cover this new feature.
Here's the example output from the new feature:
<format 'i'>
(gdb) bt
#0 Func1 (n=42, p=0x40432e "hogehoge") at main.cpp:5
#1 0x00000000004041fa in main (argc=1, argv=0x7fffffffdff8) at main.cpp:19
(gdb) x/-4i 0x4041fa
0x4041e5 <main(int, char**)+11>: mov %rsi,-0x10(%rbp)
0x4041e9 <main(int, char**)+15>: lea 0x13e(%rip),%rsi
0x4041f0 <main(int, char**)+22>: mov $0x2a,%edi
0x4041f5 <main(int, char**)+27>: callq 0x404147
<format 'x'>
(gdb) x/-4xw 0x404200
0x4041f0 <main(int, char**)+22>: 0x00002abf 0xff4de800 0x76e8ffff 0xb8ffffff
(gdb) x/-4
0x4041e0 <main(int, char**)+6>: 0x7d8910ec 0x758948fc 0x358d48f0 0x0000013e
gdb/ChangeLog:
* NEWS: Mention that GDB now supports a negative repeat count in
the 'x' command.
* printcmd.c (decode_format): Allow '-' in the parameter
"string_ptr" to accept a negative repeat count.
(find_instruction_backward): New function.
(read_memory_backward): New function.
(integer_is_zero): New function.
(find_string_backward): New function.
(do_examine): Use new functions to examine memory backward.
(_initialize_printcmd): Mention that 'x' command supports a negative
repeat count.
gdb/doc/ChangeLog:
* gdb.texinfo (Examining Memory): Document negative repeat
count in the 'x' command.
gdb/testsuite/ChangeLog:
* gdb.base/examine-backward.c: New file.
* gdb.base/examine-backward.exp: New file.
PR python/19819 concerns some unused global variables in
py-xmethods.c. This patch deletes the unused globals.
Tested by rebuilding.
2016-06-09 Tom Tromey <tom@tromey.com>
PR python/19819:
* python/py-xmethods.c (invoke_method_name)
(py_get_result_type_method_name, py_invoke_method_name): Remove.
(gdbpy_initialize_xmethods): Don't initialize
py_invoke_method_name, py_get_result_type_method_name.
Eclipse CDT now supports enabling execution recording using two methods
(full and btrace) and both formats for btrace (bts and pt). In the
event that recording is enabled behind the back of the GUI (by the user
on the command line, or a script), we need to know which method/format
are being used, so it can be correctly reflected in the interface. This
patch adds this information to the =record-started async record.
Before:
=record-started,thread-group="i1"
After:
=record-started,thread-group="i1",method="btrace",format="bts"
=record-started,thread-group="i1",method="btrace",format="pt"
=record-started,thread-group="i1",method="full"
The "format" field is only present when the current method supports
multiple formats (only the btrace method as of now).
gdb/ChangeLog:
* NEWS: Mention the new fields in =record-started.
* common/btrace-common.h (btrace_format_short_string): New function
declaration.
* common/btrace-common.c (btrace_format_short_string): New
function.
* mi/mi-interp.c (mi_record_changed): Output method and format
fields in the =record-started record.
* record-btrace.c (record_btrace_open): Adapt record_changed
notification.
* record-full.c (record_full_open): Likewise.
* record.c (cmd_record_stop): Likewise.
gdb/doc/ChangeLog:
* gdb.texinfo (GDB/MI Async Records): Document method and
format fields in =record-started.
* observer.texi (record_changed): Add method and format
parameters.
gdb/testsuite/ChangeLog:
* gdb.mi/mi-record-changed.exp: Adjust =record-started output
matching.
gdb/ChangeLog:
2016-06-02 Jon Turney <jon.turney@dronecode.org.uk>
* windows-nat.c (handle_output_debug_string): Return type of
gdb_signal_from_host() is gdb_signal, not an int.
(windows_get_exec_module_filename): Add pointer casts for C++.
gdb/gdbserver/ChangeLog:
2016-06-02 Jon Turney <jon.turney@dronecode.org.uk>
* win32-low.c (win32_create_inferior): Add pointer casts for C++.
This fixes PR python/18984.
The bug is that gdbpy_solib_name uses GDB_PY_LL_ARG, whereas it should
use GDB_PY_LLU_ARG to avoid overflow.
Built and tested on x86-64 Fedora 23.
2016-06-02 Tom Tromey <tom@tromey.com>
PR python/18984:
* python/python.c (gdbpy_solib_name): Use GDB_PY_LLU_ARG.
2016-06-02 Tom Tromey <tom@tromey.com>
PR python/18984:
* gdb.python/py-shared.exp: Add solib_name test.
... and fix Ctrl-C races.
The current remote-fileio.c SIGINT/EINTR code can lose Ctrl-C --
there's a period where SIG_IGN is installed as signal handler, for
example.
Since:
- remote.c no longer installs a custom SIGINT handler;
- The current remote-fileio.c SIGINT handler is basically the same as
the default SIGINT handler (event-top.c:handle_sigint), in
principle, except that instead of setting the quit flag, it sets a
separate flag.
I think we should be able to completely remove the remote-fileio.c
SIGINT handler, and centralize on the quit flag, thus fixing the
Ctrl-C race.
gdb/ChangeLog:
yyyy-mm-dd Pedro Alves <palves@redhat.com>
* remote-fileio.c (remote_fio_ctrl_c_flag, remote_fio_sa)
(remote_fio_osa)
(remote_fio_ofunc, remote_fileio_sig_init, remote_fileio_sig_set)
(remote_fileio_sig_exit, remote_fileio_ctrl_c_signal_handler):
Delete.
(remote_fileio_o_quit_handler): New global.
(remote_fileio_quit_handler): New function.
(remote_fileio_reply): Check the quit flag instead of the custom
'remote_fio_ctrl_c_flag' flag. Restore the quit handler instead
of changing the SIGINT handler.
(do_remote_fileio_request): Override the quit handler instead of
changing the SIGINT handler.
Patch 7eb895307f53 Skip unwritable frames in command "finish"
skips non-writable frames in addition to tailcall frames.
If skip_tailcall_frames already returns NULL, skip_unwritable_frames
will be called with a NULL frame and crash in get_frame_arch. This is
caught by gdb.btrace/tailcall-only.exp.
Further, if we ever end up with a mixture of tailcall and non-writable
frames, we may not skip all of them, as intended.
Loop over skip_tailcall_frames and skip_unwritable_frames as long as at least
one of them makes progress.
gdb/
* infcmd.c (skip_finish_frames): New.
(finish_command): Call skip_finish_frames.
As reported in PR 19998, after type ctrl-c, GDB hang there and does
not send interrupt. It causes a fail in gdb.base/interrupt.exp.
All targets support remote fileio should be affected.
When we type ctrc-c, SIGINT is handled by remote_fileio_sig_set,
as shown below,
#0 remote_fileio_sig_set (sigint_func=0x4495d0 <remote_fileio_ctrl_c_signal_handler(int)>) at /home/yao/SourceCode/gnu/gdb/git/gdb/remote-fileio.c:325
#1 0x00000000004495de in remote_fileio_ctrl_c_signal_handler (signo=<optimised out>) at /home/yao/SourceCode/gnu/gdb/git/gdb/remote-fileio.c:349
#2 <signal handler called>
#3 0x00007ffff647ed83 in __select_nocancel () at ../sysdeps/unix/syscall-template.S:81
#4 0x00000000005530ce in interruptible_select (n=10, readfds=readfds@entry=0x7fffffffd730, writefds=writefds@entry=0x0, exceptfds=exceptfds@entry=0x0,
timeout=timeout@entry=0x0) at /home/yao/SourceCode/gnu/gdb/git/gdb/event-top.c:1017
#5 0x000000000061ab20 in stdio_file_read (file=<optimised out>, buf=0x12d02e0 "\n\022-\001", length_buf=16383)
at /home/yao/SourceCode/gnu/gdb/git/gdb/ui-file.c:577
#6 0x000000000044a4dc in remote_fileio_func_read (buf=0x12c0360 "") at /home/yao/SourceCode/gnu/gdb/git/gdb/remote-fileio.c:583
#7 0x0000000000449598 in do_remote_fileio_request (uiout=<optimised out>, buf_arg=buf_arg@entry=0x12c0340)
at /home/yao/SourceCode/gnu/gdb/git/gdb/remote-fileio.c:1179
we don't set quit_serial_event,
do
{
res = gdb_select (n, readfds, writefds, exceptfds, timeout);
}
while (res == -1 && errno == EINTR);
if (res == 1 && FD_ISSET (fd, readfds))
{
errno = EINTR;
return -1;
}
return res;
we can't go out of the loop above, and that is why GDB can't send
interrupt.
Recently, we stop throwing exception from SIGINT handler
(remote_fileio_ctrl_c_signal_handler)
https://sourceware.org/ml/gdb-patches/2016-03/msg00372.html, which
is correct, because gdb_select is interruptible. However, in the
same patch series, we add interruptible_select later as a wrapper
to gdb_select, https://sourceware.org/ml/gdb-patches/2016-03/msg00375.html
and it is not interruptible (because of the loop in it) unless
select/poll-able file descriptors are marked.
This fix in this patch is to call quit_serial_event_set, so that we can
go out of the loop above, return -1 and set errno to EINTR.
2016-06-01 Yao Qi <yao.qi@linaro.org>
PR remote/19998
* remote-fileio.c (remote_fileio_ctrl_c_signal_handler): Call
quit_serial_event_set.
https://sourceware.org/bugzilla/show_bug.cgi?id=19893
I've traced the main source of the problem to pieced_value_funcs.coerce_ref not being
implemented. Since gdb always assumes references are implemented as pointers, this
causes it to think that it's dealing with a NULL pointer, thus breaking any operations
involving synthetic references.
What I did here was implementing pieced_value_funcs.coerce_ref using some of the synthetic
pointer handling code from indirect_pieced_value, as Pedro suggested. I also made a few
adjustments to the reference printing code so that it correctly shows either the address
of the referenced value or (if it's non-addressable) the "<synthetic pointer>" string.
I also wrote some unit tests based on Dwarf::assemble; these took a while to make
because in most cases I needed a synthetic reference to a physical variable. Additionally,
I started working on a unit test for classes that have a vtable, but ran into a few issues
so that'll probably go in a future patch. One thing that should definitely be fixed is that
proc function_range (called for MACRO_AT_func) will always try to compile/link using gcc
with the default options instead of g++, thus breaking C++ compilations that require e.g. libstdc++.
gdb/ChangeLog:
* dwarf2loc.c (coerce_pieced_ref, indirect_synthetic_pointer,
fetch_const_value_from_synthetic_pointer): New functions.
(indirect_pieced_value): Move lower half to indirect_synthetic_pointer.
(pieced_value_funcs): Implement coerce_ref.
* valops.c (value_addr): Call coerce_ref for synthetic references.
* valprint.c (valprint_check_validity): Return true for synthetic
references. Also, don't show "<synthetic pointer>" if they reference
addressable values.
(generic_val_print_ref): Handle synthetic references. Also move some
code to print_ref_address.
(print_ref_address, get_value_addr_contents): New functions.
gdb/testsuite/ChangeLog:
* gdb.dwarf2/implref.exp: Rename to...
* gdb.dwarf2/implref-const.exp: ...this. Also add more test statements.
* gdb.dwarf2/implref-array.c: New file.
* gdb.dwarf2/implref-array.exp: Likewise.
* gdb.dwarf2/implref-global.c: Likewise.
* gdb.dwarf2/implref-global.exp: Likewise.
* gdb.dwarf2/implref-struct.c: Likewise.
* gdb.dwarf2/implref-struct.exp: Likewise.
This patch adds tests for emit operations with 64 bit values. It takes
special care to avoid mistakes that one could make on a 32bit architecture
using 64bit values.
gdb/testsuite/ChangeLog:
* gdb.trace/trace-condition.exp: Add 64bit tests.
This patch add variable length tests for emit_ref by reading the variable
passed as argument of 8 to 64 bit.
gdb/testsuite/ChangeLog:
* gdb.trace/trace-condition.c (marker): Adapt signature to 8 to 64
bits types.
(main): Adapt to 8 to 64 bits types.
* gdb.trace/trace-condition.exp: Add new tests.
This patch moves conditional tests that were done in ftrace.exp to
trace-condition.exp.
Note that emit_ref is now tested by the anarg local variable there is no
need to test the register directly.
All emit calls have been tested using asserts before / after the move, to
ensure that the tests cover the same functions.
Note that these function were not covered before and are still not:
emit_gt_goto, emit_lt_goto, emit_pop, emit_unsigned_less.
gdb/testsuite/ChangeLog:
* gdb.trace/ftrace.exp (test_ftrace_condition): Remove.
Move condition tests...
* gdb.trace/trace-condition.exp: Here.
In trace-condition.exp, tests are done by doing a conditional tracepoint
and validating that the trace contains all the frames that could be
collected if that condition is true.
E.g. test_tracepoints $trace_command "21 + 21 == 42" 10
This will always return true and collect the 10 frames possible to collect
with the test program.
However, if the condition evaluation is broken such that the condition is
unconditional we will not notice this problem.
This patch adds counter-cases to such conditions like so:
$trace_command "21 + 11 == 42" 0
This way such a problem would be noticed.
gdb/testsuite/ChangeLog:
* gdb.trace/trace-condition.exp: Add counter-case tests.
Local variables in lambdas are not accessible
https://sourceware.org/bugzilla/show_bug.cgi?id=15231
GDB: read_lexical_block_scope
/* Ignore blocks with missing or invalid low and high pc attributes. */
[...]
if (!dwarf2_get_pc_bounds (die, &lowpc, &highpc, cu, NULL))
return;
But sometimes there is:
FAIL: gcc-5.3.1-6.fc23.x86_64
<2><92>: Abbrev Number: 11 (DW_TAG_lexical_block)
<3><9c>: Abbrev Number: 13 (DW_TAG_structure_type)
<9d> DW_AT_name : (indirect string, offset: 0x3c): <lambda()>
[...]
Where DW_TAG_lexical_block has no attributes. Such whole subtree is currently
dropped by GDB while I think it should just import all its children DIEs.
It even XFAIL->XPASSes gdb.ada/out_of_line_in_inlined.exp:
commit 0fa7fe506c242b459c4c05d331e7c7d66fb52390
Author: Joel Brobecker <brobecker@adacore.com>
out of line functions nested inside inline functions.
So I have removed that xfail.
gdb/ChangeLog
2016-05-30 Jan Kratochvil <jan.kratochvil@redhat.com>
PR c++/15231
* dwarf2read.c (enum pc_bounds_kind): Add PC_BOUNDS_INVALID.
(process_psymtab_comp_unit_reader, read_func_scope): Adjust callers.
(read_lexical_block_scope): Import DIEs from bare DW_TAG_lexical_block.
(read_call_site_scope): Adjust callers.
(dwarf2_get_pc_bounds): Implement pc_bounds_invalid.
(dwarf2_get_subprogram_pc_bounds, get_scope_pc_bounds): Adjust callers.
gdb/testsuite/ChangeLog
2016-05-30 Jan Kratochvil <jan.kratochvil@redhat.com>
PR c++/15231
* gdb.ada/out_of_line_in_inlined.exp: Remove xfails.
* gdb.dwarf2/dw2-lexical-block-bare.exp: New file.
Make the code (maybe) more readable + primarily prepare it for [patch 2/2]
enum extension.
This change should have no code change impact.
gdb/ChangeLog
2016-05-30 Jan Kratochvil <jan.kratochvil@redhat.com>
Code cleanup: dwarf2_get_pc_bounds: -1/0/+1 -> enum
* dwarf2read.c (enum pc_bounds_kind) New.
(dwarf2_get_pc_bounds): Use it in the declaration.
(process_psymtab_comp_unit_reader): Adjust caller. Rename has_pc_info
to cu_bounds_kind.
(read_func_scope, read_lexical_block_scope, read_call_site_scope):
Adjust callers.
(dwarf2_get_pc_bounds): Use enum pc_bounds_kind in the definition.
(dwarf2_get_subprogram_pc_bounds, get_scope_pc_bounds): Adjust callers.
Standardize the QCatchSyscalls NEWS entry.
gdb/ChangeLog
2016-05-29 Jan Kratochvil <jan.kratochvil@redhat.com>
* NEWS (QCatchSyscalls): Remove the parameter. Include ...
(QCatchSyscalls:1 in qSupported) ... this separate entry which got
deleted.
If the testsuite is run with a DejaGnu version that predates the fix
from last year:
[PATCH] DejaGnu kills the wrong process due to PID-reuse races
http://lists.gnu.org/archive/html/dejagnu/2015-07/msg00005.html
... gdb.threads/attach-many-short-lived-threads.exp fails randomly,
often. Other tests randomly fail due to that issue too, but this one
is _much_ more exposed.
DejaGnu 1.6 was released meanwhile, which includes that DejaGnu fix,
and also some distros backported the fix too.
So skip the test when run with older/broken DejaGnus.
gdb/testsuite/ChangeLog:
2016-05-27 Pedro Alves <palves@redhat.com>
* gdb.threads/attach-many-short-lived-threads.exp (bad_dejagnu):
New procedure.
(top level): Call it, and bail out of DejaGnu is known to be bad.
gdb/doc/ChangeLog:
* gdb.texinfo (General Query Packets): Move the description of the
response before the long list of the specific 'read' and 'write'
requests.
When evaluating an expression with EVAL_AVOID_SIDE_EFFECTS if the value
we return is forced to be of type not_lval then GDB will be unable to
take the address of the returned value.
Instead, we should properly initialise the LVAL of the returned value.
This commit builds on two previous commits 2520f728b710 (Forward
VALUE_LVAL when avoiding side effects for STRUCTOP_STRUCT) and
ac775bf4d35b (gdb: Forward VALUE_LVAL when avoiding side effects for
STRUCTOP_PTR), which in turn build on ac1ca910d74d (Fixes for PR
exp/15364).
This commit is currently untested due to my lack of access to an OpenCL
compiler, however, if follows the same pattern as the first two commits
mentioned above and so I believe that it is correct.
gdb/ChangeLog:
* opencl-lang.c (evaluate_subexp_opencl): If
EVAL_AVOID_SIDE_EFFECTS mode, forward the VALUE_LVAL attribute to
the returned value in the STRUCTOP_STRUCT case.
Assume that we have a C program like this:
struct foo_type
{
int var;
} foo;
struct foo_type *foo_ptr = &foo;
int
main ()
{
return foo_ptr->var;
}
Then GDB should be able to evaluate the following, however, it currently
does not:
(gdb) start
...
(gdb) whatis &(foo_ptr->var)
Attempt to take address of value not located in memory.
The problem is that in EVAL_AVOID_SIDE_EFFECTS mode,
eval.c:evaluate_subexp_standard always returns a not_lval value as the
result for a STRUCTOP_PTR operation. As a consequence, the rest of
the code believes that one cannot take the address of the returned
value.
This patch fixes STRUCTOP_PTR handling so that the VALUE_LVAL
attribute for the returned value is properly initialized. After this
change, the above session becomes:
(gdb) start
...
(gdb) whatis &(foo_ptr->var)
type = int *
This commit is largely the same as commit 2520f728b710 (Forward
VALUE_LVAL when avoiding side effects for STRUCTOP_STRUCT) but applied
to STRUCTOP_PTR rather than STRUCTOP_STRUCT. Both of these commits are
building on top of commit ac1ca910d74d (Fixes for PR exp/15364).
gdb/ChangeLog:
* eval.c (evaluate_subexp_standard): If EVAL_AVOID_SIDE_EFFECTS
mode, forward the VALUE_LVAL attribute to the returned value in
the STRUCTOP_PTR case.
gdb/testsuite/ChangeLog:
* gdb.base/whatis.c: Extend the test case.
* gdb.base/whatis.exp: Add additional tests.
Ulrich pointed out that an earlier patch had misspelled
HAVE_LIBPYTHON2_4, adding an extra "_". This caused a build failure.
This patch fixes the bug.
2016-05-25 Tom Tromey <tom@tromey.com>
* python/py-value.c (value_object_as_number): Use correct spelling
of HAVE_LIBPYTHON2_4.
Variable "show" was hardcoded to zero for pointer and reference types.
This implementation didn't allow a correct "whatis" print
for those types and results in same output for "ptype" and "whatis".
Before:
(gdb) whatis t3p
type = PTR TO -> ( Type t3
integer(kind=4) :: t3_i
Type t2 :: t2_n
End Type t3 )
After:
(gdb) whatis t3p
type = PTR TO -> ( Type t3 )
2016-05-25 Bernhard Heckel <bernhard.heckel@intel.com>
gdb/Changelog:
* f-typeprint.c (f_type_print_base): Replace 0 by show.
gdb/testsuite/Changelog:
* gdb.fortran/type.f90: Add pointer variable.
* gdb.fortran/whatis_type.exp: Add whatis/ptype of pointers.
As as result of printing only the outer elements of nested structures,
some testcases have to be added to check for corner cases with VLA's.
2016-05-25 Bernhard Heckel <bernhard.heckel@intel.com>
gdb/testsuite/Changelog:
* gdb.fortran/vla-type.exp: Access elements in nested structs.
According to the typeprint's description, the level of details is
decreased by one for the typeprint of elements of a structure.
Before:
(gdb) ptype t3v
type = Type t3
integer(kind=4) :: t3_i
Type t2
integer(kind=4) :: t2_i
Type t1
integer(kind=4) :: t1_i
real(kind=4) :: t1_r
End Type t1 :: t1_n
End Type t2 :: t2_n
End Type t3
After:
(gdb) ptype t3v
type = Type t3
integer(kind=4) :: t3_i
Type t2 :: t2_n
End Type t3
2016-05-25 Bernhard Heckel <bernhard.heckel@intel.com>
gdb/Changelog:
* f-typeprint.c (f_type_print_base): Decrease show by one.
gdb/testsuite/Changelog:
* gdb.fortran/type.f90: Add nested structures.
* gdb.fortran/whatis-type.exp: Whatis/ptype nested structures.
* gdb.fortran/derived-type.exp: Adapt expected output.
* gdb.fortran/vla-type.exp: Adapt expected output.
According to the typeprint's description, elements of a structure
should not be printed when show is < 1.
This variable is also used to distinguish the level of details
between "ptype" and "whatis" expressions.
Before:
(gdb) whatis t1v
type = Type t1
integer(kind=4) :: t1_i
real(kind=4) :: t1_r
End Type t1
After:
(gdb) whatis t1v
type = Type t1
2016-05-25 Bernhard Heckel <bernhard.heckel@intel.com>
gdb/Changelog:
* f-typeprint.c (f_type_print_base): Don't print fields when show < 0.
gdb/testsuite/Changelog:
* gdb.fortran/whatis_type.exp: Adapt expected output.
Level of indentation was not proper handled when printing
the elements type's name.
Before:
type = Type t1
integer(kind=4) :: var_1
integer(kind=4) :: var_2
End Type t1
After:
type = Type t1
integer(kind=4) :: var_1
integer(kind=4) :: var_2
End Type t1
2016-05-25 Bernhard Heckel <bernhard.heckel@intel.com>
gdb/Changelog:
* f-typeprint.c (f_type_print_base): Take print level into account.
gdb/testsuite/Changelog:
* gdb.fortran/print_type.exp: Fix expected output.
* gdb.fortran/whatis_type.exp: Fix expected output.
This patch fixes PR python/17386.
The bug is that gdb.Value does not implement the Python __index__
method. This method is needed to convert a Python object to an index
and is used by various operations in Python, such as indexing an
array.
The fix is to implement the nb_index method for gdb.Value.
nb_index was added in Python 2.5. I don't have a good way to test
Python 2.4, but I made an attempt to accomodate it.
I chose to use valpy_long in all cases because this simplifies porting
to Python 3, and because there didn't seem to be any harm.
Built and regtested on x86-64 Fedora 23.
2016-05-24 Tom Tromey <tom@tromey.com>
PR python/17386:
* python/py-value.c (value_object_as_number): Add
nb_inplace_floor_divide, nb_inplace_true_divide, nb_index.
2016-05-24 Tom Tromey <tom@tromey.com>
PR python/17386:
* gdb.python/py-value.exp (test_value_numeric_ops): Add tests that
use value as an index.
Python 2's PyNumberMethods has nb_inplace_divide, but Python 3 does
not. This patch adds it for Python 2.
This buglet didn't cause much fallout because the only non-NULL entry
in value_object_as_number after this is for valpy_divide; and the
missing slot caused it to slide up to nb_floor_divide (where
nb_true_divide was intended).
2016-05-24 Tom Tromey <tom@tromey.com>
* python/py-value.c (value_object_as_number): Add
nb_inplace_divide for Python 2.
PR python/17981 notes that gdb.breakpoints() returns None when there
are no breakpoints; whereas an empty list or tuple would be more in
keeping with Python and the documentation.
This patch fixes the bug by changing the no-breakpoint return to make
an empty tuple.
Built and regtested on x86-64 Fedora 23.
2016-05-23 Tom Tromey <tom@tromey.com>
PR python/17981:
* python/py-breakpoint.c (gdbpy_breakpoints): Return a new tuple
when there are no breakpoints.
2016-05-23 Tom Tromey <tom@tromey.com>
* python.texi (Basic Python): Document gdb.breakpoints return.
2016-05-23 Tom Tromey <tom@tromey.com>
PR python/17981:
* gdb.python/py-breakpoint.exp (test_bkpt_basic): Add test for
no-breakpoint case.
PR gdb/19194 points out a typo in the documentation. I'm checking
this in as obvious.
2016-05-24 Tom Tromey <tom@tromey.com>
PR gdb/19194:
* gdb.texinfo (gdb man): Fix typo.
When GDB attaches to a process, it looks at the /proc/PID/task/ dir
for all clone threads of that process, and attaches to each of them.
Usually, if there is more than one clone thread, it means the program
is multi threaded and linked with pthreads. Thus when GDB soon after
attaching finds and loads a libthread_db matching the process, it'll
add a thread to the thread list for each of the initially found
lower-level LWPs.
If, however, GDB fails to find/load a matching libthread_db, nothing
is adding the LWPs to the thread list. And because of that, "detach"
hits an internal error:
(gdb) PASS: gdb.threads/clone-attach-detach.exp: fg attach 1: attach
info threads
Id Target Id Frame
* 1 LWP 6891 "clone-attach-de" 0x00007f87e5fd0790 in __nanosleep_nocancel () at ../sysdeps/unix/syscall-template.S:84
(gdb) FAIL: gdb.threads/clone-attach-detach.exp: fg attach 1: info threads shows two LWPs
detach
.../src/gdb/thread.c:1010: internal-error: is_executing: Assertion `tp' failed.
A problem internal to GDB has been detected,
further debugging may prove unreliable.
Quit this debugging session? (y or n)
FAIL: gdb.threads/clone-attach-detach.exp: fg attach 1: detach (GDB internal error)
From here:
...
#8 0x00000000007ba7cc in internal_error (file=0x98ea68 ".../src/gdb/thread.c", line=1010, fmt=0x98ea30 "%s: Assertion `%s' failed.")
at .../src/gdb/common/errors.c:55
#9 0x000000000064bb83 in is_executing (ptid=...) at .../src/gdb/thread.c:1010
#10 0x00000000004c23bb in get_pending_status (lp=0x12c5cc0, status=0x7fffffffdc0c) at .../src/gdb/linux-nat.c:1235
#11 0x00000000004c2738 in detach_callback (lp=0x12c5cc0, data=0x0) at .../src/gdb/linux-nat.c:1317
#12 0x00000000004c1a2a in iterate_over_lwps (filter=..., callback=0x4c2599 <detach_callback>, data=0x0) at .../src/gdb/linux-nat.c:899
#13 0x00000000004c295c in linux_nat_detach (ops=0xe7bd30, args=0x0, from_tty=1) at .../src/gdb/linux-nat.c:1358
#14 0x000000000068284d in delegate_detach (self=0xe7bd30, arg1=0x0, arg2=1) at .../src/gdb/target-delegates.c:34
#15 0x0000000000694141 in target_detach (args=0x0, from_tty=1) at .../src/gdb/target.c:2241
#16 0x0000000000630582 in detach_command (args=0x0, from_tty=1) at .../src/gdb/infcmd.c:2975
...
Tested on x86-64 Fedora 23. Also confirmed the test passes against
gdbserver with "maint set target-non-stop".
gdb/ChangeLog:
2016-05-24 Pedro Alves <palves@redhat.com>
PR gdb/19828
* linux-nat.c (attach_proc_task_lwp_callback): Mark the lwp
resumed, and add the thread to GDB's thread list.
testsuite/ChangeLog:
2016-05-24 Pedro Alves <palves@redhat.com>
PR gdb/19828
* gdb.threads/clone-attach-detach.c: New file.
* gdb.threads/clone-attach-detach.exp: New file.
Working on the fix for gdb/19828, I saw
gdb.threads/attach-many-short-lived-threads.exp fail once in an
unusual way. Unfortunately I didn't keep debug logs, but it's an
issue similar to what's been fixed in remote.c a while ago --
linux-nat.c was not fetching the pending status from the right place.
gdb/ChangeLog:
2016-05-24 Pedro Alves <palves@redhat.com>
PR gdb/19828
* linux-nat.c (get_pending_status): If the thread reported the
event to the core and it's pending, use the pending status signal
number.
Hacking the gdb.threads/attach-many-short-lived-threads.exp test to
spawn thousands of threads instead of dozens, and running gdb under
perf, I saw that GDB was spending most of the time in find_lwp_pid:
- captured_main
- 93.61% catch_command_errors
- 87.41% attach_command
- 87.40% linux_nat_attach
- 87.40% linux_proc_attach_tgid_threads
- 82.38% attach_proc_task_lwp_callback
- 81.01% find_lwp_pid
5.30% ptid_get_lwp
+ 0.10% ptid_lwp_p
+ 0.64% add_thread
+ 0.26% set_running
+ 0.24% set_executing
0.12% ptid_get_lwp
+ 0.01% ptrace
+ 0.01% add_lwp
attach_proc_task_lwp_callback is called once for each LWP that we
attach to, found by listing the /proc/PID/task/ directory. In turn,
attach_proc_task_lwp_callback calls find_lwp_pid to check whether the
LWP we're about to try to attach to is already known. Since
find_lwp_pid does a linear walk over the whole LWP list, this becomes
quadratic. We do the /proc/PID/task/ listing until we get two
iterations in a row where we found no new threads. So the second and
following times we walk the /proc/PID/task/ dir, we're going to take
an even worse find_lwp_pid hit.
Fix this by adding a hash table keyed by LWP PID, for fast lookup.
The linked list embedded in the LWP structure itself is kept, and made
a double-linked list, so that removals from that list are O(1). An
earlier version of this patch got rid of this list altogether, but
that revealed hidden dependencies / assumptions on how the list is
sorted. For example, killing a process and then waiting for all the
LWPs status using iterate_over_lwps only works as is because the
leader LWP is always last in the list. So I thought it better to take
an incremental approach and make this patch concern itself _only_ with
the PID lookup optimization.
gdb/ChangeLog:
2016-05-24 Pedro Alves <palves@redhat.com>
PR gdb/19828
* linux-nat.c (lwp_lwpid_htab): New htab.
(lwp_info_hash, lwp_lwpid_htab_eq, lwp_lwpid_htab_create)
(lwp_lwpid_htab_add_lwp): New functions.
(lwp_list): Tweak comment.
(lwp_list_add, lwp_list_remove, lwp_lwpid_htab_remove_pid): New
functions.
(purge_lwp_list): Rewrite, using htab_traverse_noresize.
(add_initial_lwp): Add lwp to htab too. Use lwp_list_add.
(delete_lwp): Use lwp_list_remove. Remove htab too.
(find_lwp_pid): Search in htab.
(_initialize_linux_nat): Call lwp_lwpid_htab_create.
* linux-nat.h (struct lwp_info) <prev>: New field.
Hacking the gdb.threads/attach-many-short-lived-threads.exp test to
spawn thousands of threads instead of dozens, I saw GDB having trouble
keeping up with threads being spawned too fast, when it tried to stop
them all. This was because while gdb is doing that, it updates the
thread list to make sure no new thread has sneaked in that might need
to be paused. It does this a few times until it sees no-new-threads
twice in a row. The thread listing update itself is not that
expensive, however, in the Linux backend, updating the threads list
calls linux_common_core_of_thread for each LWP to record on which core
each LWP was last seen running, which opens/reads/closes a /proc file
for each LWP which becomes expensive when you need to do it for
thousands of LWPs.
perf shows gdb in linux_common_core_of_thread 44% of the time, in the
stop_all_threads -> update_thread_list path in this use case.
This patch simply makes linux_common_core_of_thread avoid updating the
core the thread is bound to if the thread hasn't run since the last
time we updated that info. This makes linux_common_core_of_thread
disappear into the noise in the perf report.
gdb/ChangeLog:
2016-05-24 Pedro Alves <palves@redhat.com>
PR gdb/19828
* linux-nat.c (linux_resume_one_lwp_throw): Clear the LWP's core
field.
(linux_nat_update_thread_list): Don't fetch the core if already
known.
... as it's _much_ faster.
Hacking the gdb.threads/attach-many-short-lived-threads.exp test to
spawn thousands of threads instead of dozens to stress and debug
timeout problems with gdb.threads/attach-many-short-lived-threads.exp,
I saw that GDB would spend several seconds just reading the
/proc/PID/smaps file, to determine the vDSO mapping range. GDB opens
and reads the whole file just once, and caches the result, but even
that is too slow. For example, with almost 8000 threads:
$ ls /proc/3518/task/ | wc -l
7906
reading the /proc/PID/smaps file grepping for "vdso" takes over 15
seconds :
$ time cat /proc/3518/smaps | grep vdso
7ffdbafee000-7ffdbaff0000 r-xp 00000000 00:00 0 [vdso]
real 0m15.371s
user 0m0.008s
sys 0m15.017s
Looking around the web for hints, I found a nice description of the
issue here:
http://backtrace.io/blog/blog/2014/11/12/large-thread-counts-and-slow-process-maps/
The problem is that /proc/PID/smaps wants to show the mappings as
being thread stack, and that has the kernel iterating over all threads
in the thread group, for each mapping.
The fix is to use the "map" file under /proc/PID/task/PID/ instead of
the /proc/PID/ one, as the former doesn't mark thread stacks for all
threads.
That alone drops the timing to the millisecond range on my machine:
$ time cat /proc/3518/task/3518/smaps | grep vdso
7ffdbafee000-7ffdbaff0000 r-xp 00000000 00:00 0 [vdso]
real 0m0.150s
user 0m0.009s
sys 0m0.084s
And since we only need the vdso mapping's address range, we can use
"maps" file instead of "smaps", and it's even cheaper:
/proc/PID/task/PID/maps :
$ time cat /proc/3518/task/3518/maps | grep vdso
7ffdbafee000-7ffdbaff0000 r-xp 00000000 00:00 0 [vdso]
real 0m0.027s
user 0m0.000s
sys 0m0.017s
gdb/ChangeLog:
2016-05-24 Pedro Alves <palves@redhat.com>
PR gdb/19828
* linux-tdep.c (find_mapping_size): Delete.
(linux_vsyscall_range_raw): Rewrite reading from
/proc/PID/task/PID/maps directly instead of using
gdbarch_find_memory_regions.
